1. Field of the Invention
This invention relates to a method for preventing and treating thrombosis. More particularly, this invention relates to a method for preventing and treating thrombosis in which the therapeutic agent is 5-(hydroxy-3-t-butylamino)propoxy-3,4-dihydrocarbostyril having the following formula ##EQU2##
2. Description of the Prior Art
Hitherto, developments in medicine and pharmacy have contributed to the establishment of advanced therapeutic systems, whereby a number of serious diseases have been overcome. However, no effective and reliable therapeutic agent or method has yet been established for circulatory diseases, particularly, ischemic diseases, arterioschlerosis and cerebral thrombosis. Since these circulatory diseases are often fatal, development of promising agents for preventing and treating these serious diseases has been of great concern to many people. The cause of these diseases is considered to be thrombosis as described in Hovig, T.: "Platelet Adhesion and Aggregation in Thrombosis": Countermeasures (Mammen, E. F., Anderson, G. F. & Barnhart, M. I. Eds.), p. 137 (1970); Bizzozero, J.: Virchows Arch., 90, 261 (1882); and Eberth, J. C. & Schimmelbusch, C.: Virchows Arch., 103, 39 (1886).
Thrombus is a clot formed by a coagulation of blood flowing in a blood vessel and the origin of the formation of thrombus and the symptoms caused by the thrombus are called thrombosis. A thrombus is useful in that damaged parts of a blood vessel are reinforced and in that continuous bleeding due to the activity of blood platelets as a "trigger" is prevented. On the other hand, the thrombus has negative aspects in that the thrombus obstructs the blood vessel cavity or obstructs the blood vessels of organs, limbs and the like when it is transported to other organs by blood flow thereby causing an embolus infarction. Therefore, thrombi formed in the main organs such as the heart, lungs, brain and the like are accompanied by fatal effects such as cerebral infarction (embolus), myocardiac infarction and pulmonary infarction. Further, in other diseases such as diabetes, malignant tumors, essential hypertension, valvular cardiac disease, Basedow's disease, aorta syndrome mucous tumor and the like, thrombi tend to be formed secondarily and also easily develop due to changes in the nature of blood per se, for example, coagulation acceleration state, etc. and blood vessel wall (Sozo Matsuoka, Factors for Bleeding and Thrombosis, page 206, published by Kinbara Publishing Co., 1969 and Kaname Kotake, "Thrombus Formation and Platelets", Metabolism and Disease, Vol. 10, No.2, page 118, 1973).
Factors for thrombus formation include (1) change in the nature of the blood, (2) change in the blood flow and (3) change in blood vessel wall. Reference can be made to Tadashi Maekawa, Ketsueki To Myakkan (Blood and Vessel), Vol. 1, No. 4, pp 11-24, 1970. The normal flowing blood maintains an adequate dynamic balance between aggregation and dissociation of platelets as well as between coagulation and thrombolysis of the blood. Thrombosis can occur when this balance is lost due to stress or abnormal physiological conditions.
In recent years, the modern diet has very likely tended to induce arterioschlerosal disorders with a result in a possible increase in the occurrence of thrombosis. Under these circumstances, the development of chemo-therapeutics for treating and preventing thrombosis has been greatly desired. For thrombosis, it is more effective to prevent the formation of thrombi by inhibiting further development of thrombi. Disorders induced by the secondarily formed thrombi can also be improved by administering therapeutic agents for alleviating the thrombi in combination with therapy for the fundamental disease.